PD-1 Proteins

Programmed cell death protein 1 (PD-1, CD279) is a type I transmembrane receptor expressed on T cells and B cells and a key immune checkpoint in the immunoglobulin superfamily. PD-1 binds the B7 family ligands PD-L1 and PD-L2, and PD-L1 overexpression on tumor cells can suppress immune responses by inhibiting T cell activity. Blocking the PD-1/PD-L1 interaction is a validated strategy in cancer immunotherapy and underlies widely used PD-1 inhibitor drugs. Conigen provides recombinant PD-1 proteins designed to support receptor/ligand and antibody binding studies, assay development, and antibody discovery, including formats that enable investigation of biologically relevant receptor interactions.

Human PD-1 His-Avi ELISA

Example QC data shown. See individual product pages and datasheets for target-specific QC results.

Available formats

Soluble PD-1 ectodomain dimer CSPâ„¢ (Conigen Soluble Protein)

  • Human (His-Avi)

Available PD-1 Products

ProductTagSpeciesProduct CodeDetailshf:tax:product_taghf:tax:pa_species
PD1His-AviHumanCSP-24093-03Show detailshis-avihuman

Applications

  • Antibody discovery and characterization (screening and specificity testing for PD-1–targeting antibodies)
  • Immune checkpoint interaction studies (ELISA workflows for antibody and PD-1/PD-L1 receptor/ligand binding assays, including competition/blocked-binding formats)
  • Binding kinetics and affinity studies (SPR and BLI assays for PD-1 interactions with antibodies and PD-L1 ligand)
  • Assay and reagent development (workflow optimization for PD-1/PD-L1 binding assays and screening reagents)
  • Animal immunization (RUO) (as an immunogen to support generation of PD-1-targeting antibodies)

Quality Control and Specifications

Quality Control Testing

  • Purity assessment (greater than 90% dimer formed as determined by SDS-PAGE under reducing and non-reducing conditions)
  • Bioactivity testing (binding activity confirmed by ELISA and SPR for PD-1 interactions with PD-L1 ligand and PD-1–specific antibodies—which supports functional checkpoint engagement)
  • Lot-specific documentation provided in downloadable product datasheets

Product Specifications

  • Format: extracellular domain cis-dimers of PD1
  • Expression host: HEK293T (mammalian)
  • Construct: soluble extracellular domain (ECD) dimer fused with a proprietary dimer motif to mimic the native conformation
  • Formulation: 0.22 μm filtered PBS, pH 7.4
  • Storage & shipping: shipped frozen on dry ice; store at −80°C

About Conigen Soluble Proteins

Engineered dimeric proteins with quaternary structures

  • Enhances receptor/ligand binding
  • Increase functional activity
  • Improve binding avidity for better detection sensitivity
  • Compact size dimer motif
  • Fc-free to avoid FcR binding
  • Glycan-free dimer motifs to avoid target epitope masking

 

Learn more about Conigen Soluble Proteins

FAQs

Recombinant PD-1 is widely used in immunology and oncology research, particularly in studies focused on immune checkpoint regulation and cancer immunotherapy. Common applications include:

  • Antibody and therapeutic development
  • PD-1/PD-L1 interactions studies
  • Immunoassays and analytical applications

Our PD-1 is provided as a dimer and engineered to replicate the native, cell-surface conformation of PD-1 more closely than the monomeric ectodomain.

In practice, our dimeric PD-1 provides:

  • Higher binding potency
  • Improved assay sensitivity 
  • Wider assay windows

Yes, our recombinant PD-1 has been validated for use in binding assays, including ELISA-based PD-1-specific antibody binding assays and PD-L1 ligand binding assays.

Yes, matched PD-1 and PD-L1 recombinant protein pairs are available upon request. Please contact us with your species, tag, and format requirements.

PD-1 is supplied in PBS and is shipped on dry ice. Upon receipt, it should be stored at – 80°C. For optimal stability we recommend aliquoting the protein into smaller volumes before freezing to avoid repeated freeze-thaw cycles.

For short term use, the protein may be stored at 4°C for a limited period. For long-term storage, keep the protein at -80°C for up to 12 months. Avoid vigorous mixing; gently invert or pipette to mix if needed.

PD-1 is available from Conigen in the human form with a His-Avi tag.

Additional tags such as Fc, Flag, HA, or Myc or formats such as biotinylation can be provided through custom expression to match your assay or conjugation needs.

Yes. PD-1 proteins can be customized through Conigen’s CSP â„¢ platform. For custom PD-1 formats (alternate tags, variants, or assay-specific constructs), email [email protected] or submit a request through our Custom Project form.

Lead time varies by format and scale. Catalog PD-1 can be ordered directly and will ship within 2-3 business days of sales order receipt. 

Custom PD-1 and larger orders will follow a defined project workflow, but will generally be shipped 4-6 weeks following request. Contact us for a precise delivery estimate.

Need help selecting the right PD-1 format for your assay?